Bill Gates still richest American, Forbes says

NEW YORK (Reuters) - Things are on the up for U.S. billionaires with more than half of them adding to their net worth in a year which once again saw Bill Gates as the richest of them all, Forbes magazine said on Wednesday.

Gates, founder of Microsoft, was the richest person in the United States for the 17th year in a row with an estimated worth of $54 billion, up $4 billion from last year.